Near-elliptic core polarization-maintaining photonic crystal fiber: Modeling birefringence characteristics and realization

We investigate the modal birefringence behavior of a near-elliptic core index-guiding photonic crystal fiber (PCF) by using the first-order perturbation correction technique of mode analysis combined with semivectorial mode-field convergence method. The algorithm requires simple formulation, yields reasonably accurate results, and is efficient as needed for a design analysis; it is also applicable to any index-guiding regular structure/PCFs. The efficacy of our design tool has been verified with otherwise known solutions. Using this as a design recipe, we have realized PCFs with high birefringence characteristics.